Leases (Schedule of Future Minimum Lease Payments for Non-cancellable Leases) (Details) (PUGET SOUND ENERGY, INC., USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
PUGET SOUND ENERGY, INC.
Operating
2013	$ 16,238
2014	15,199
2015	15,257
2016	17,175
2017	17,064
Thereafter	81,944
Total minimum lease payments	162,877
Capital
2013	8,160
2014	8,160
2015	8,160
2016	2,718
2017	0
Thereafter	0
Total minimum lease payments	$ 27,198

Amount of minimum lease payments for capital leases.

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